Automatic thermostatic control device



Feb. 10, 1953 I B. s. COPPING 2,628,032

AUTOMATIC THERMOSTATIC CONTROL DEVICE- Filed Nov. 19, 1948 3 Sheets-Sheet l a E j /0 q T fl{ "-(-Q m. W MM Min-2170i i 46 .BPLZCG G Capping Feb. 10, 1953 B. G. COPPING AUTOMATIC THERMOSTATIC CONTROL DEVICE 3 Sheets-Sheet 2 Filed Nov. 19, 1948 [Hz E1770!" Bruce G. Co v vz'ny Hfljys Feb. 10, 1953 B. G. COPPING 2,628,032 AUTOMATIC THERMOSTATIC CONTROL DEVICE Filed Nov. 19, 1948 5 Sheets-Sheet 5 ma E W 6a 60 m3 m9 /02 /pg 2 /zz E 9 Bruce G (70 0 00 Patented Feb. 10, 1953 UNITED STATES PATENT oFFI cE Bruce Gray Copping, Cuyahoga- Falls, -Ohio,.assignor to Don ManufacturingCompany, Chi-- cago, 111., a corporation .of Illinois Application November 19, 1948; -Serial No. 60,852

11 Claims.

Myinvention relatesto thermostatic appliances,

system are provided witha plurality of, individual outlets to spaces or zones whichare to be temperature conditioned. Positioned in each outlet is althermostatically controlled. shutter forthe purpose of automatically controlling the now of heating or cooling air'into a given space. Shutter controlswhich are responsive to space temperatures generallyurge a shutter to. a closed position as room temperature rises when the air distribution system is us'edfor heating purposes. Conversely, if the air distribution system is to be used for cooling purposes, theshutt'er is urged to an open position as the space temperaturerises. Thus, in the pastgshutter' con trols'have had to be built'for heating or for coolin'g but could not be used to control both heating'and cooling. My invention provides means forautomatically converting" a" single thermo statically controlled shutter from a' heating control'unit to acooling control unit or vice versa.--

This; thereforeyforms oneobject of my-inven tion.

Anotherobject of my invention is Y to provide improvedthermostaticmeans for-controlling the flow of'temperature conditioned air into spaces which-are'either to be heated or cooled.

Anotherobject of my invention is to provide control dampers which will allow adequate ventilation 'when the operating temperature range is such asto normallyinactivate thermostatic control.-

Still another object of my invention'is to-provide -a self-converting thermostatically regulated damper control which converts small linear displacement into relatively large angular displacement thereby eifecting accurate control within a very limited compact space.

It-is aiurther object of my invention :to provide a thermostatic appliance which automat-w ically-lconve'rtsito usexas a heating control or a cooling :controlwhich isof simplified mechanical construction and which requires a -minimumof.

manual adjustment.

Another object of my invention is the-pro-- vision'of a device that is convenient .andsatisfactory forits intended purpose;

Many other obj ects. will appear from the fol lowing description: and the appendedrclaimu For a more complete understandingaof the in--- vention, reference maybehad to the followingde,-- tail description and accompanying-- drawings, a in which Figure 1 isafront view=-ofa=shutter: installa tion embodyingz oneflform. of the presentinven tion;

Figuret 2 is.'a-..side1:elevation of the-shutter installation shown in Figure 1;

Figure 3 is a slightly:enlarged-view of the shutter-installation shown: in Figure 1 with louvre I shell or. grill sectionremoved to 1showthejcomplete thermostatic control device incorporating;

the principles 'of my. .invention;

Figure 4 is a bottom:view showing.additional details of-theshutter installa'tionand controldevice shown in Figure X 3 Figure 5 is an end view-showing:constructionsdetails of: the! shutter installation :and .control device shown in :Figure 13; 1 I

Figure 6 is an enlarged cross-sectionftakenv through" the. entire length. ofthe thermostatic control device showingsthe'idetails of :the device;

Figure .7 iswa: cross-section taken :through a' portion of: the: thermostatic? control device on a-plane represented by:-'section;-VII' -VII; Fige;

Figure 8 isan enlarged view' 'of oner-end. ofthe=-r control device' and is sectionalized was in 1 Figure 6 to show the operative details of certain members during one phase of itszoperation Figure 9. is' a cross-sectional: view taken;

th-rough section 1IX IX; Figure 4 Figure 10 is across-sectional. view through" section Zi -X of Figure 4; and

Figure 11 is" a cross-sectionalwview I through section Xl-XI of Figure-4.1:

As shown on .thevdrawingsr Referringvfirst-toFiguresyi and 2 of: the draw-"'- ings, a thermostatically:controlled ventilator is herein indicated-=- as comprising: "an air register shown generally at I ll and a temperature respone This ventilator is associated with 'a delivery duct-12,-

sive; :regulator indicated generally at l l-.

the discharge endof which is'defined by an openingin a wall or other supporting structure generally'indicated at I3.- In :"this' particular -em-- bodiment 1-1 have; shown how 1 a suitable connection of the ventilator to the duct may be accomplished by a plurality of screws I4 passing through a louvred mounting plate I5, a ventilator frame l6 (Figure 3), a rubber gasket l1 and into the wall I3.

The construction of the inner portion of the ventilator of Figures 1 and 2 is shown in further detail in Figures 3, 4 and 5, as well as in Figure 10. It will be noted that the frame H5 is shown as providing an opening l8. A shutter l9, comprising an upper blade 2| disposed above the opening and a bottom blade 22 disposed below the opening, as may most clearly be seen in Figure 10, is longer and wider than the opening |8, thereby efiecting a sealed engagement with the frame l6 when the shutter H] is in a closed position, thereby effectively controlling communication between the duct l2 and the space which is to be temperature conditioned. The blades 2| and 22 are joined as shown on Figures 4 and by rivets 23 or other suitable connecting means to form a flange 24 by bending the blades 2| and 22 into an L shape.

The shutter I9 is positioned in the opening H! by means of a cord suspension arrangement, the details of which will now be described.

Afiixed to one end of the shutter |9 (left side of Figures 3 and 4) are a pair of fingers 25 and 26 suitably bent to form a double flange and slit to provide notched receptacles in said flanges for anchoring and accommodating a suspension wire 21, a suspension wire 28, a return spring 29, and a return spring 3|. The fingers 25 and 26 are joined to the flange 24 of the shutter l3 and to each other by a plurality of rivets 32 or other suitable means.

Disposed at right angles to the ventilator frame I6 is a flanged metal end support 33 which is secured to the frame l6 by spot welding, or other suitable means. The suspension wire 21 and the suspension wire 28 extend from the fingers 25 and 26, respectively, to the end support 33 and are retained longitudinally by means of a plurality of nubbins 34 which are press clamped to the end portions of the suspension wires 21 and 23. The nubbins bear against the notch receptacles of fingers 25 and 26 and positioning plate 31.

The suspension wires 21 and 2B are restrained against movement within a transverse plane defined by the notched receptacles of the fingers 25 and 26 by a wire bent to form a clamp 35, which engages the nubbins 34 in a locking relationship. The opposite ends of the suspension wires 2'! and 23 are positioned within a vertical end support notch 36 and a positioning plate 31.

Thus, it will be noted that the suspension wires 21 and 28 are disposed in one plane at their points of contact with the end support 33 and are disposed at their points of contact with the fingers 25 and 26 in a plane which is substantially normal to said one plane when the shutter I3 is closed. This results in a partial twist of the suspension wires which, in turn, imparts a torsional force to the shutter i9 and tends to rotate the shutter toward an open position when the shutter I9 is tensioned rightward.

Rotative opening displacement of shutter I3 is limited by a stop 20 which is soldered or otherwise attached in a suitable position to the frame structure. (Dotted lines in Figure 10 show the shutter Is at maximum open position.)

Referring to Figures 3, 4 and 11, the return spring 23 is positioned alongside the end support 33 and is hooked into the notched receptacle of the finger 26 and attached to an car 38 project ing from the end support 33.

The return spring 3| is positioned alongside the end support 33 and is hooked into the notched receptacle of the finger 25 and attached to an ear 39 projecting from the end support 33.

Inasmuch as the notch receptacles contained in the fingers 25 and 26 lie in two difierent planes, the spring tension of the return springs 29 and 3| produce a twisting moment, the resultant of which operates to subject the shutter Hi to a torsional force. The quantitative proportions of this force will vary as shutter I9 is moved through different angular displacements. The operative effect of such a return spring assembly is to bias the shutter suspension assembly toward the closed position whenever th rightward tension on the shutter I9 is diminished, until a condition of torsional balance is obtained. Accurate thermostatic control of the suspension assembly is thereby made possible.

The other end of the shutter |9 (right side- Figures 3 and 4) is supported by a tension wire 4| secured to the flange 24 by means of an adjustable wire socket arrangement, indicated generally at 46, comprising a socket clamp 42, a hollow standard 43 having threads out upon a substantial portion of one end and notched upon the other end, and a socket nut 45 threaded so as to engage the threads on the standard 43 in a nut and bolt relationship. The flange 24 has an appropriate opening 49 and a slit 5| formed therein (right sideFigure 4) to accommodate the adjustable wire socket assembly.

The notched end of the standard 43 engages the slit 5| of the flange 24 in a sliding fit thereby restrictively supporting the shutter IS with respect to relative angular displacement. The tension wire 4| passes through the hollow standard 43 and the socket nut 45 but at its outer extremity (rightFigure 4) is connected to a thermostatic control device and at its inner extremity, is clamped securely by socket clamp 42.

It should be apparent that this arrangement facilitates simple manual adjustment of the effective operating length of the tension cord 4|. Inasmuch as the socket nut 45 bears against the wall defining the opening 43 in the flange 24 and the socket clamp 42 operates to lock the tension wire 4| by bearing against the walls of the hollow standard 43, a manual adjustment of the socket nut 45 may be effected to selectively alter the longitudinal alignment of the cord suspension mechanism. Adjustment of the length of the cord suspension in this manner enables a factory calibration of the shutter unit. In other words, a predetermined tension may be established in the unit in accordance with the efiective operating limits of the thermostatic control device associated with the shutter suspension assembly.

I have also found that a calibration setting made with the described arrangement may be locked into place to prevent changes in adjustment by sealin the threaded fit of the socket nut 45 and the standard 43 with Glyptal or some other suitable cement.

My shutter cord suspension arrangement is preferably equipped with 2l-strand stainless steel aircraft type cable since I have found by experiment that this cable achieves results nearest to those expected from a theoretically perfect cord because of its relatively small opposition to bending and twisting,

As may best be seen on Figures 3. 4 and 10, the

frame l 6 is flanged upward-aton end to form an end support ili; Affixed thereto .is-a. box .41 which isspot welded to the end support 45 through a pair of toes 52. The box 47 forms .an enclosure 53 for housing a portion of the thermostatic controldevice H, as well as to form a supporting structure for th shutter means.

Aspacer bar as is disposed between the'end' support 33 and the box 3? to act not only as a spacer member but as a compression means in the shutter -frame structure. This improved frame structure adequately accommodates the tensional stress variations attendant-upon the use of a cord suspended shutter.

It-may be noted at this pointthat the enclosure 53 i communicates with the delivery duct l2- througlra pair of spaced openings 54 which are formed in the ventilator frame It bybending a pair of tabs 55 inwardly into the enclosure 53.

The. interior'thermostatic area of regulator It is. in communication with the enclosure 53 through a pair of spaced openings (not shown) formed in the housings? by bending a pair of filed May 8,1943,"and Serial No. 25,837, filed May 8,. 19.48, now Patents 2g523A98'and 2,523,499 issued September 26, 1950.

Referring now to Figure 6; a thermostatic control device is indicated having essentially three temperature responsive components which, for purposes of this disclosure, shall be referred to andindicated-generally upon the drawings as a room thermostat 60,;a tensioning. thermostat 80 and a reversing thermostat IMF.

The. room thermostat 69 has, a cylindrical adjusting knobv 6 I. preferably made of molded plastic so that functional, grip configurations may be formed intheknob... The. knob i6 Lis also. threaded at. its inner extremities asshown. at 62 for purposes of. achieving a threaded.engagementwitha threaded -,portion 63 of. a thermostat housing t l. Atitsouterextremities, the knob v ii terminates in a; plurality of, inwardly extending 11135.65,

which may, also be seen in the end view of Fig? ure Disposedwithin the, chamber formed by. the cylindricaliorm ofthe; adjusting knob ti is a temperature sensitive device of the type which operates to vary the linear alignmentof its members in response to changes in temperature.

Preferably, this device is of the so-called Verneti.

typewherein a-cha-ngein volume of a'material duringiphysical transformation from one state to another inresponse to temperature variations is utilized to displacea pi along a l ear path- A' .Verneti device of. this class is indicated gen orally atfifi,as-comprisinga:piston fill and-a body 68..

The ribs 6520f. theknob, 6 i; engage; .the body, 68 to..provide:radial: positioning-1 pport as. well. as

topreventiputward longitudinal displacement of the; .fVernet; body 168.-1

The piston 61 engages? a spacer indicated gene,

described, preferably, of the Vernet'type.

.85 of the prongs it is a spring sleeve 92.

extending fins H and a:rodrportion:indicatediiate 10; The fins 1| are disposed onan outsidediann eter approximately the same as the. insidesdiami-zl eter of the knob 6| and operate, therefordtoposi tion the spacer (it in the center of the room' ther-s:

mostat tfl assemblyr The-housing 6G is of die-cast construction and H has an abutment 72 which positions the control device inthe end support 5M The-housing iitlis cylindrical for a portion-of its length and 'defines cated at it which serve as parts of the supporting structure for the tensioning thermostat indicated generally at 86;

Positioned within the spac 15 is a-conical spring it. The smaller conical sectionof-the i spring is is capped by a retainer H, which, as may be seen from the drawings, is essentially a" hollow cylinder with wings or fins on one end; The 'bore of retainer T. is of such a diameter as to accommodate the rod iii ofthe spacer 69 andis inside-threaded as at E8 so as to provide for a 4 threaded engagement with tension fork 19.

Turning now to the tensionin -thermostatfll as indicated generally in Figure-6, a substantially cylindrically-shaped space is indicated at 8| which is formed by the fork-shaped prongs 14- and a pair of projecting walls fit-oftension-iorh "59 (Figure 7).

Disposed within'thespace 8l-is a'temperaturesensitive device of the general class previously As appears in Figures 6 and 7, a Vernet thermostat is indicated as comprising a body 83 and a pis-v ton 8 One end of the space 8| is partially terminated by a pair of arcuate shoulders 85 formed in the prongs "is. The other end of the space BI is terminated by a shoulder 86' (Figure 7) formedin the tension fork F9 and a support yoke 81. The support yoke 8? is secured to the prongs M by a plurality of machine screws 88 and is drilled and threaded through a neck portion 89 to receive in threaded engagement a set screw Si which is positioned within the neck portionfldior the purpose of engaging and retaining the piston-.84 in a counterbore 93 formed in one end of the set screw 9 i. I

shouldered against the Vernet device body 83 and slidingly supported by the arcuate shoulders As in-. dicated .inFigures 6 and '7, the spring sleeve 92 is. a flanged cylindrical sleeve, one end of which being capable of receiving a reduced cylindrical portion of the body 83 and having a hole in its other end for the accommodation. of a .pin iii]; A coil spring 94 is coiled about the sleeve 92 andbears against the arcuate shoulders 85 on one end and against the flanged portion of the spring sleeve 92 on the other end.

It should be noted that the tensioning thBIIDO-J- stat 8t communicates with the conditioning air passing through the ventilator through a pair of airports 95 formed in the projecting walls 82.

Positioned between the projecting walls 82 of the tension fork '59 is a bobbin Hi2. Together, the, bobbin IE2 and the walls 82 define a cylindrical, space M33 which houses the reversing thermostat are.

Terminating the space lilii at one end is a plug;

emflygatw sgigcomprismga m m dia11 q I 0 5; which. may be secured ,as; shown'on Fig-ure -6.

7 by drilling and tapping the bobbin I02 and the plug I04 for threaded engagement with a plurality of machine screws I05. Plug I04 is also provided with a hole I06 large enough to accommodate the tension wire 4| but small enough to provide an adequate bearing surface for engaging a socket clamp I'I which is permanently pressed upon the tension wire 4I.

Disposed within the space I 03 is a coil spring I08 which cooperates with a temperature sensitive device similar to those previously described, preferably of the Vernet type. Such a device is shown in Figures 6 and 7 as comprising a main body I09 having a shoulder II I, a body flange I I2 and a piston H3.

Terminating the space I03 on the other end is the wall portion of bobbin I02 formed to provide a. boss I I4 which is drilled and tapped as at H5 to receive in threaded connection the pin IN. The pin IOI has a flange 99 on its other end suitable for selective seating within the spring sleeve 92. The piston H3 of the Vernet device contained in the space I03 engages the boss H4 of the bobbin I02 during certain phases of operation, as will be described in separate portion of this disclosure.

The projecting walls 82 are appropriately drilled and tapped to receive in threaded relationship two pair of pin stops indicated at H6 and H1.

Positioned to the right (as appears on Figures 6 and 7) of the pin stops I I1 is an adjustable flange I I8 which is of a general cylindrical configuration and has a flange face suitable for engagement with the pin stops H1 and an inside diameter large enough to freely pass the pin IOI. The outer surface of the flange cylinder H9 is threaded so as to engage a yoke I I9.

Extending from the extremities of the arms of the yoke H9 are two beams I20 supported and arranged to pivotally oscillate about a pair of cylindrical fulcrum pins I2I and pivotally connect to the yoke I I9 by means of a pair of cylindrical pins I22. The innermost extremities of the beam I20 are rounded into a rolling cam surface as at I23.

The reversing thermostat I00 communicates with the conditioning air passing through the ventilator through a pair of air ports I24 formed in the projecting walls 82.

Operation In a complete heating and cooling ventilation system to which my invention would be applied, three different temperature conditions may exist in the conditioning air flowing through the ducts of the distribution system. If the system is operating as a heating unit, the temperature of the conditioning air will be over 90' F. If the system is operating as a cooling unit, the temperature of the conditioning air will be less than 65 F. If neither heating nor cooling is required, the temperature of the conditioning air circulating for purposes of ventilation lies between the limits of 65 and 90 F. This latter condition shall be referred to as the neutral phase.

The reversing thermostat I00 is designed to have its activity between 70 and 80 F. At 80 F. its temperature responsive element is fully expanded (Figures 6 and 7). Under this condition, the body I09 and the piston H3 tend to oppose each other, therefore the piston H3 bears against the inner surface of the boss H4 portion of the bobbin I02, while the body I09 tends to move to the left (in the position shown on the drawings).

The shoulder I I I of the body I09 is urged against the coil spring I 00 and the flange H2 of the body I09 is carried along until it comes in contact with the pin stops H6.

If the temperature of the conditioned air is 70 F. or less, the temperature responsive element of the reversing thermostat I00 is fully contracted (Figure 8). The piston H3 is retracted into the inside of the body I09 thereby permitting the coil spring I08 to urge the body I09 toward the right. Under these conditions the flange H2 is moved away from the pin stops I I6.

The tensioning thermostat is designed to have its activity between 80 and 90 F. At 90 its temperature responsive elements are fully expanded (Figure 7). Therefore, at temperatures of 90 or higher, the piston 84 and the body 83 tend to oppose one another. The piston 84 thrusts into the counterbore 93 and bears against the set screw 9| which is firmly secured in the neck portion 89 of the support yoke 81 which, in turn, is secured by the machine screws 08 in the prongs 14 of the housing 64. Thus, the body 83 tends to move to the left but is limited when the shoulder of body 83 bears against the spring sleeve 92 which, in turn, is urged against the coil spring 94. The coil spring 94 is compressed because it is confined by the arcuate shoulders of the prongs I4. It should be noted that the spring sleeve 92 slides through the shoulders 85 and around the pin IOI so that the flange 99 of the pin Iill no longer bears against the spring sleeve 92.

At 80, or less, tensioning thermostat 80 is in its fully contracted position (Figure 6). Under these conditions the piston 84 is loosely supported in the counterbore 93 of the set screw 9| and the coil spring 94 urges the spring sleeve 92 to the right against the resistance of the thermostatic element body 83 until it is ultimately limited when it encounters the flange 99 of the pin IOI.

It should be noted that although the thermostats 80 and I00 are in communication with and respond to the temperature of the conditioned air within the ducts of the air distribution system, the room thermostat 50 is designed to respond to the average temperature of the air in the space or zone which is to be temperature conditioned and partakes of the space temperature by virtue of the air movement induced to flow from the room or zone into the thermostat assembly.

As may be seen on the drawing air flow into the space 15 between the ribs 65 and then to the enclosure 53 of the aspirator structure. Thus, variations in temperature of the room to be temperature conditioned will result in relative linear displacement of the piston 01 and the body 68. These displacements are transmitted to the rod portion I0 of the spacer 69 and thence to the tension fork I9.

Referring particularly to Figure 6, it should be noted that the conical spring I6, confined by the annular shoulder I3 of the housing 04, bears against the retainer II which is in threaded relationship with the tension fork I9, thereby tending to urge the room thermostat assembly 60 toward the right. Inasmuch as the adjusting knob BI is threadedly engaged with the housing 64 at 62 and since the body 68 is confined by the ribs 05 of the knob 6|, rotative manipulation of the knob 61 will alter the lineal relationship between the tension fork I9 and the room thermostat 60 and thus alter the position assumed by the shutter I9 for any given relative linear displacement between the piston 61 and the body 68,

thereby permitting a selective calibration of ""knob BI with respect'to the operating temperature range of the'room thermostat.

-1Heating "If='the"di'stribution system is" being used for "heating purposes, the conditioning air is heated to at least 90 F. 'In this range the reversing thermostat I and'the tensioning thermostat 80 are fully expanded (Figure 7). The room thermostat members 60 undergo relative linear displacement in response to room temperature variations transmitted through the tension fork I9 to the projecting walls 82, then through pin Neutral If the temperature of the conditionedair'drops to 80, the air distribution system is in the so- 'calle'd neutral phase.

The reversing thermostat I00 is fully expanded so there is no change in "that unit. However, the tensioning thermostat 80 is now in its fully contracted condition Fig.

' ure 6), therefore, coil spring 94 has urged the springsleeve 92 to the right so that the flange 199 of the pin IOIis seated against the ends of the .spring sleeve 92.

It should be noted at this point that only a slight motion of the spring sleeve 92 is necessary to engage or disengage the flange 99 and the extent vof the displacement necessary may be .manually adjusted by a suitable positioning of the set screw 9I in the neck portion 84 of the support yoke 01.

Thus, engagement or disengagement of the flange 99 with the spring sleeve 92 may be made to occur in the first small relative motion of the thermostatic device body 83 andthe piston 84.

When the flange 99 engages the spring sleeve 9'2,it is apparent that the expansive force of the coil spring 94 is transmitted through the spring sleeve 92 and the flange 99 to the pin I 0| and thence to the bobbin I02 threa'dedly engaged with the pin IOI at II5. Thus, the bobbin I02 tends to the right and places the tension wire 4| under increased tension causing the shutter I9 to. open thereby permittinga continuous free flow of ventilating air from the air distribution system into .thegivenspace.

right which, in turn, engages the flange 99 of the pin IOI and causes the bobbin I02 to tend to the right. Inasmuchas the reversingthermostat .is fully contracted, thecoil spring I99 has-urged the body I09 toward the right so that the flange II2 has moved away fromrthe pin stops IIB'toward engagement with the end-surfaces I23 of thebeams I29. 'I'heipin stops IITen-gagethe adjustable i -flange 'I I 81 which is in threaded relation'ship with-the. yoke II9,"therefore,:wh'en a .temperature decrease :occursin the-room, space -.-or'.zone,theprojecting walls182 of the tension 10 fork 81 are urged to the right by the action of the coil spring' I6 conjoin'tly with the' action of the temperature responsive'elements of the room 1 thermostat 60. The displacement of the projecting walls 82 "-isimparted to the adjustable flange II8' bythe pin stops Ill and thence to the yoke I I9causing the beams I 20 to pivot; about the ful- =crum pins 'I2I, thereby engaging and pressing leftward the flange II2 atthe cam surfaces I23. 10"

I02 'by the body I09 and the coil spring I08 and Theresulting force'is transmitted to the bobbin tends to decrease the tension'created on the tension cord 4| by the coil spring 94, thus causing shutter I 9 to close.

When a temperature increase occurs in the room, space or zone, the projecting' walls 82 will tend toward the left and'move thepin stops II'I leftward. This permits a'leftward motion of the adjustable flange H8 and the yoke II9 and'al- 'lOWs the beams I20to"rotate about the fulcrum 'pins' 'I2I and the cam surfaces I23 tomove rightward. This, in'turn, permits the"bobbinI02 to move'rightward under the urging of'the coil spring 94 and'thus tension thecord 4| causing 'the shutter I9 toopen.

Attention is drawn to the 'fact' that the ad- "justable' flange IIB may be selectively positioned ibyvirtue oi the threaded engagement with the F positively. by appropriate manual adjustment.

,From the foregoing itshould be 'seen that I have "provided an automatic thermostatically controlled ventilator capable of responding to the temperature requirement of spaces or zones served by anairtemperature conditionin distribution system .even though the spaces are likely to have variable requirements necessitatingalternate heating, cooling, or only ventilation.

Itshould be further apparent that I have provided a temperature responsive. device which secures automatic control of the heating, cooling or ventilating requirements-of various spaces or zones by means of a controller responsive'to the temperature conditions of the various zones and in which the controller is automatically changed from or to conditions suitable for heating operations, cooling operations or ventilating operations in response to the temperature oftheconditioning air.

It will be apparent that many changes will suggest-themselves to those skilled in the art. I, therefore, desire to be limited only by the scope of the appended claims and the prior art.

.I claim. as my invention:

1. In av control device associated with a. temperature conditioning air system serving a, plurality of spaces of the type wherein adamper means supported by acord suspension having been urged toward anopen position by a predetermined torsional stress iscontrolled by selectively varyingsaid torsional stress with axial the type which operates-tovary the linear alignment of its members associated" with first; said :device aforementioned toperable to :tensionally stress 'saiclrcord suspension within: a determinable temperature range so as to maintain said damper open within determinable limits, a third temperature sensitive device of the type which operates to vary the linear alignment of its members and a leverage arrangement comprising a yoke and two beams, said beams pivotallv connected with housing of said first device; said third device associated with said leverage arrangement and these two in turn assoc ated with said first and second devices operable to reverse the normal operation of said shutter within a determinable tem erature range so as to cause said shutter to open when room temperature rises.

2. In a heating and cooling ventilator register of the type wherein a dam er means is supported by a cord suspens on, said damper being normally ur ed to an open po ition bv a tersional stress and said damper being regulated by controlling said torsional stress, the improvement comprising, in combination, a control mechanism having three tem erature sensit ve devices of the type which operate to vary the linear alignment of their members in respon e to temperature variations and a leverage arrangement assoc ated therewith, the nu ber one device normally o erable over a manually adjustable range to close said damper means upon a rise in temperature in a room being heated, number two device adiusted to be actuated within a limited temperature range and normally operable to o en said damper when a room is neither to be heated or cooled. number three device adjusted to be actuated within a determinable temperature ran e so as to en age said lever arrangement connected with housing of number one device, the joint action of said devices and lever arran ement operable to o en said damper means upon a rise in temperature of the room to be cooled within determinable temperature limits.

3. A thermostatic regulating device in control of a torsionally balanced, cord suspended damper positioned in a duct leading from an air temperature conditioning system to a given space, comprising, in combination, a room thermostat having a dimension varying in response to temperature changes, an aspirator structure associated with said room thermostat to permit said thermostat to partake of average room temperature, a

. spring means associated with said room thermostat, a rotatively adiustable shell retainer cooperating with said spring means and said thermostat ior establishing and controlling a calibrated actuating range for said thermostat, a link member connecting said thermostat to said cord suspended damper, said thermostat normally operable to close said damper upon a rise of room temperature under heating operation, a tensioning thermostat of the type which operates to vary the linear alignment of its members in response to temperature changes, a coil spring cooperating with said tensioning thermostat, said tensioning thermostat and said spring associated with said room thermostat and said damper operable to open said damper within determinable limits of a selective temperature range by spring biasing of said cord suspended damper, a reversing thermostat of the type which operates to vary the linear alignment of its members in response to temperature changes, a pair of pivotally mounted lever arms connected with the housing structure of said room thermostat, a manually adju=table supporting structure connected to said lever arms, a plurality of pin stops attached to 12 7. said link member of said room thermostat operable to engage said adjustable supporting structure, said reversing thermostat and said lever arms cooperating with said room thermostat within a pre-determined temperature range to overcome said spring bias of said tensioning thermostat causing said damper to open upon a rise in room temperature under cooling operation.

4. As an article of manufacture, an auxiliary mechanism for a thermostatic control device of the type described herein, said mechanism comprising. in combination, a hollow cylindrical knob threadedly received in a die-cast metal member, said member being shaped cylindrically on one end and having a pair of parallel prongs extending in a direction opposite said knob, a spring means housed in said metal member, said spring means and a first thermostatic device located in said knob adjustably related in resilient engagement within said metal member and said knob by suitable spacer means, a yoke member attached to said spacer means having a pair of parallel legs extending between said parallel prongs, said legs and said prongs defining a chamber for housing a second thermostatic device and a second spring means, said second device and said second spring means resiliently engageable through a spring sleeve in said chamber, a flanged pin selectively engageable with said spring sleeve and threadedly connected to a bonnet disposed between said legs of said yoke, said bonnet and said legs defining a compartment for housing a third thermostatic device and a third spring means, said third spring and said third device resiliently engageable within the confines of said bonnet, a plug fitted in said bonnet for receiving a tension cord of a cord suspended shutter, a leverage mechanism fixed in said prongs, and pin stops arranged in said legs for engaging said third thermostatic device and said leverage mechanism, said auxiliary mechanism operable to transmit linear variations of said first thermostatic device to said tension cord in response to temperature reductions when said second thermostatic device is activated and operable to transmit a tension to said tension cord when said second thermostatic device is inactivated and further operable to transmit linear variations of said first thermostatic device to said tension cord through said leverage mechanism in response to temperature increments when said second and third thermostatic devices are inactivated.

5. A thermostatic regulating device in control of a torsionally balanced, cord-suspended, butterfiy-type damper positioned in a duct leading from an air temperature conditioning system to a given I space comprising, in combination, a yoke memher engaging a first thermostatic device operable to change relative linear displacement in response to variations in a first predetermined temperature range, said yoke having a pair of extending parallel legs, a housing for said first thermostatic device having a pair of extending parallel prongs, a bonnet located between said legs of said yoke connected to a single tension cord of said cord suspended damper, a second thermostatic device associated with a spring means engaging said prongs and said yokefor applying a fixed, predetermined amount of force to said tension cord in response to temperatures in a second predetermined range, a leverage mechanism pivotally mounted in said prongs, a third thermostatic device associated with a spring means engaging said bonnet, said third thermostatic device operable to apply a fixed, predetermined amount of force against said leverage mechanism in response to temperatures in a third predetermined range thereby reversing the axial direction of said linear displacement of said first thermostatic device, said regulating device operable to selectively open and close said damper in response to temperature changes for heating control in said first range, ventilating control in said second range and cooling control in said third range of temperature.

6. In a duct control device for a temperature conditioning system, a rotatable shutter adapted to control the flow of a temperature conditioned fluid through a duct, support means including twisted suspension members to carry said shutter and to pre-load the shutter torsionally, a first tensioning means connected to said suspension members including a temperature sensitive device of the type which operates to vary the linear aligmnent of its members in response to changes in temperature, normally operable to close said shutter when the room temperature rises, a second tensioning means including a temperature sensitive device of the type which operates to vary the linear alignment of its members associated with said first tensioning means to tensionally stress said suspension members in a determinable temperature range to maintain said shutter open within determinable limits, a third tensioning means including a temperature sensitive device of the type which operates to vary the linear alignment of its members and coupling means connecting said first and said third tensioning means to reverse the normal operation of said shutter within a predetermined temperature range to open said shutter when the room temperature rises.

7. In a duct control device as defined in claim 6, said first tensioning means including adjustment means to selectively vary the effective range thereof.

8. In an air flow controller, a housing defining an air passage adapted to carry temperature conditioned air, a rotatable shutter in control of the air flow through said passage, suspension members between said shutter and the housing being twisted to torsionally load the shutter and tensioning means connected to the suspension members for controlling rotation of the shutter by variably tensioning the suspension members to change the torsion load of the shutter, said tensioning means including a first thermostatic means to deliver variable tensioning loads in response to temperature variations to close said shutter in response to a temperature increase for heating operation and a second thermostatic load delivering means coupled to said first thermostatic means to reverse the normal operation thereof throughout a predetermined temperature range, thereby to open said shutter in response to a temperature increase for cooling operation.

9. In an air flow controller as defined in claim 8, said tensioning means further including additional thermally responsive load-delivering means to hold said shutter open throughout a predetermined temperature range for ventilating operation.

10. In an air flow controller, a housing defining an air passage, a rotatable shutter in control of air flow through said passage, suspension members between the shutter and the housing and being twisted to torsionally load the shutter and tensioning means connected to the suspension members for controlling rotation of the shutter by variably tensioning the suspension membersto change the torsional load on the shutter, said tensioning means including a thermostatic means to deliver variable tensioning loads to close said shutter in response to temperature variations, said tensioning means further including additional thermally responsive load delivering means to hold said shutter open throughout a predetermined temperature range for ventilating operation.

11. Air flow control apparatus comprising, a damper, a duct controlled thereby, suspension means rotatably suspending said damper in said duct, torsional means stressing said damper towards one position of balance, a first thermostatic means connected to said damper and overcoming the torsional stress on said damper by a force directed axially of said damper in response to temperature variations throughout a first predetermined temperature range for turning the damper towards another position as for heating control, a second thermostatic means connected to said damper and overcoming the torsional stress on said damper by a predetermined force directed axially to said damper in response to temperatures in a second predetermined range for holding said damper open as for ventilating purposes, and a third thermostatic means connected to said damper and overcoming the torsional stress on said damper by a force reversely applied axially to the damper in response to temperature variations in a third predeterminedrange for turning the damper towards another position as for cooling control.

BRUCE GRAY COPPING.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,656,372 Fitts Jan. 17, 1928 1,833,950 Modine Dec. 1, 1931 2,241,108 Akers May 6, 1941 2,318,706 Newton May 11, 1943 2,447,560 Branson Aug. 24, 1948 2,463,600 Carson Mar. 8, 1949 2,523,499 Copping Sept. 26, 1950 

